Scheduled Recording Test

with microMARS

You can schedule microMARS recordings using a mission start time,mission end time and a duty cycle interval. It's a good idea to run a brief test or 'mini mission' with the scheduling features for your familiarization before first field use.

Here, we will schedule a recording with a mission start time in five minutes, recording with a duty cycle of alternating 1 minute on and 1 minute off, and a mission end time in ten minutes.

Throughout the recording, we'll leave the USB cable connected to observe the recorders activities. Let's go…

We set up our desired schedule in microMARS Reader:

In the Mission Timing tab we define the recording start and end times. Notice that the dates and times must be specified in UTC, not in local time.

In the Acoustic Recording tab we define the recording Segment Size of 1 minute, as well as the Duty Cycle time spans of 1 minute ON and OFF respectively. Notice also the other settings.

Before we write the settings to the recorder, lets get up the Raw Communication window to observe what is happening. Select View→View Raw Coms. And now write the settings Action→Write Settings. Observe the results in the right pane, which are the recorders replies to the PC commands. The time stamps are all in seconds since January 1, 1970. Note how the mission start time MST is about 289 seconds larger then the current recorder time CLOCK. That means the recording phase will start in a little under 5 minutes from now. And the mission end time RT in turn is 300 seconds larger than MST, just like we want.

To observe for this mini-mission, we leave the USB cable connected. But, since microMARS won't normally start a mission until the cable is disconnected, we need an override. Do that through the EDR command that you can enter in the field at the bottom of the Raw Com window. Here it's for recorder serial number 3. We enter $3,0,EDR and click the Send button.

The recorder will issue various reports as the mission proceeds. Watch them in the right pane or switch to a more capable terminal software such as TeraTerm (use 9600 baud). I did the later to record this activity log.

Notice also the corresponding blink patterns led_blink_patterns: Prior to the mission or recording start time, the LED will blink green once every 32 seconds. During recording, it's red at a rate corresponding to the sample rate, such as once every 5 seconds at 100,000 samples per second. Once the recording is done,it's a green blink once every 64 seconds. In the field, always watch the LED blink pattern before deployment!

OK, and that's it! In my test, the first card pair now contained three files, just like the mission reports indicated.

Trouble Shooting

Here are some scheduling related causes for having no recordings:

Mission times were specified in local time instead of UTC: If you specified the start and end time in local time rather than UTC and you are way out west, such as in Hawaii, UTC will be already considerably later. Perhaps you specified mission parameters that were actually in the past?

Time format: The time format is YYYY-MM-DD. Got the month and day confused perhaps?

Write Settings: Forgot it and the recorder doesn't know yet what you want to do?

Something Else: Watch the mission reports or the LED to find out what the problem is.